The present invention relates to a turbine housing for a turbocharger in which a gas passage is defined in a turbine wheel, chamber to introduce gas to a turbine wheel and more particularly a turbine housing for a turbocharger in which a gas passage is divided into a plurality of gas paths axially of the turbine.
Prevailing in conventional turbochargers is a concept of dividing a gas passage within a turbine housing into a plurality of gas paths so as to utilize dynamic energy as one means for improving turbocharger performance.
In some turbochargers of this type, a partition plate or plates for separating a gas passage into a plurality of gas paths are formed integral with a turbine housing. More particularly, as shown in FIGS. 1 and 2, a partition plate 2 is formed integral with a scroll-shaped inner surface of a turbine housing 1 so that a gas passage 3 is divided into gas paths 3a and 3b axially of a turbine. Reference numeral 4 represents a turbine wheel.
Such turbochargers with the integral turbine housing 1 and partition plate 2 are defective in that an inner periphery of the partition plate 2 may easily crack as shown in FIG. 1 when the plate 2 is thermally affected by a turbine wheel being operated. Because, the partition plate 2 formed integral with the turbine housing 1 cannot be thermally deformed and thermal stresses are concentrated at the partition plate 2.
In order to solve this problem, there has been proposed a construction in which a turbine housing is divided into segments and a partition plate independent of the turbine housing is partially floatably fitted between the segments. The independent partition plate is prevented from cracking when being subject to high temperatures since it can thermally deform in radial and circumferential directions. However, the circumferential deformation of the partition plate may cause at least an end face of the partition plate at a gas inlet 1' of the turbine housing to be displaced with the disadvantageous result that gases to flowing through the respective gas paths may be mixed.
In view of the above, a primary object of the present invention is to provide a turbine housing for a turbocharger in which a partition-plate receiving member is provided at a gas inlet for avoidance of admixture of gas flows and for prevention of concentration of thermal stresses.
The above and other objects, effects, features and advantages of the present invention will become more apparent from the following description of preferred embodiments thereof taken in conjunction with the accompanying drawings.